package com.codinghero.example.crawler4j;

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.security.MessageDigest;

/**
 * @author Yasser Ganjisaffar <lastname at gmail dot com>
 */
public class Cryptography {

        private static final char[] hexChars = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e',
                        'f' };

        public static String MD5(String str) {
                try {
                        MessageDigest md = MessageDigest.getInstance("MD5");
                        md.update(str.getBytes());
                        return hexStringFromBytes(md.digest());
                } catch (Exception e) {
                        e.printStackTrace();
                        return "";
                }
        }

        private static String hexStringFromBytes(byte[] b) {
                String hex = "";
                int msb;
                int lsb;
                int i;

                // MSB maps to idx 0
                for (i = 0; i < b.length; i++) {
                        msb = (b[i] & 0x000000FF) / 16;
                        lsb = (b[i] & 0x000000FF) % 16;
                        hex = hex + hexChars[msb] + hexChars[lsb];
                }
                return (hex);
        }
}

